U.S. Pat. Nos. 4,217,185, 4,242,183 and 6,352,635 B2 and U.S. Patent Application Publication 2009/0090639 describe the preparation of certain halopyridine and halopicolinic acid derivatives by the selective electrochemical reduction of the corresponding higher halogenated pyridine and picolinic acid derivatives. In this process, the silver cathode is activated by an anodization that involves increasing the potential from an initial value of zero volts to a final value of at least +0.3 volts and preferably about +0.7 volts. Because of passivation, however, the reaction rate typically slows down as conversion proceeds and it is sometimes necessary to reactivate the cathode by re-anodization to finish a batch. It would be desirable to have an improved method for activating the cathode that is more resistant to passivation and would allow shorter reaction times.